PARIS (AP) -- A rogue trader facing three years in prison for one of the biggest trading frauds in history is appealing to the French president.

Jerome Kerviel, who almost took down his bank, Societe Generale, with 4.9 billion euros in losses, has been on a months-long pilgrimage back to France after meeting the pope. He stopped his return just short of the border Saturday.

Kerviel, convicted in 2010, insists he was the victim of a system that allowed his illegal trades as long as they made money. An appeals court threw out a fine equal to his losses, but upheld his prison sentence.

Kerviel is supposed to report to start his sentence by Sunday or be considered a fugitive. He said he was appealing to French President Francois Hollande for mercy.